SEC*. XXXVt. 4. ^ERIOtfS OF DISEASES. 523 



of relieving difagreeable fenfations by this kind of 

 exertion, the fit recurs from any flight caufe. 



15. The attack of the palfy and apoplexy are 

 known to recur with great frequency about the equi- 

 noxes. 



1 6. There are numerous inflances of the effect of 

 the lunations upon the periods of infamty, whence 

 the name of lunatic has been given to thdfe afflicted 

 with this difeafe. 



IV. The critical days, in which fevers are fup- 

 pofed to terminate, have employed the attention of 

 medical philofophefs from the days of Hippocrates 

 to the prefent time. In whatever part of a lunation 

 a fever commences, which owes either its whole 

 caufe to folar and lunar influence, or to this in 

 conjunction with other caufes ; it would feem, that 

 the effect would be the greateft at the full and new 

 moon, as the tides rife higheft at thofe times, and 

 tvould be the leaft at the quadratures ; thus if a 

 fever- fit fhould commence at the new or full moon, 

 occafioned by the folar and lunar attraction dimi- 

 nifhing fome chemical affinity of the particles of 

 blood, and thence decfeafing their ftimulus on our 

 fanguifefous fyftem, as mentioned in Sect. XXXIL 

 6. this effect will daily decreafe for the firft feven 

 days, and will then increafe till about the fourteenth 

 day, and will again decreafe till about the twenty- 

 firlt day, and increafe again till the end of the lu- 

 nation. If a fever-fit from the above caufe fhould 

 commence on the feventh day after either lunation, 

 the reverfe of the above circumftances would hap-* 

 pen. Now it is probable, that thofe fevers, whofe 

 crifis of terminations are influenced by lunations, 

 may begin at one or other of the above times, 

 namely at the changes or quadratures ; though fuf- 

 ficient obfervations have not been made to afcer- 

 tain this circumftanee. Hence I conclude* that the 

 fmall-pox and mealies have their critical days, not 



VOL. I. Mm governed 



